Dynamometer adapter



SEARGE==E Oct. 13, 1964 R. w. JAY

DYNAMOMETER ADAPTER 2 Sheets-Sheet 1 Filed Sept. 14. 1960 FIG. 2

INVENTOR.

ROBERT W. JAY

ATTORNEY Oct. 13, 1964 R. w. JAY 3,152,474

DYNAMOMETER ADAPTER Filed Sept. 14. 1960 2 Sheets-Sheet 2 INVENTOR.

ROBERT W. JAY

ATTORNEY United States Patent Office 3,152,474 Patented Oct. 13, 1964 3,152,474 DYNAMOMETER ADAPTER Robert W. Jay, Linch, Wyo., assignor to Continental Oil Company, Ponca City, Okla, a corporation of Delaware Filed Sept. 14, 1960, Ser. No. 55,977

4- Claims. (Cl. 73-141) This invention relates to adapting a dynamometer to a long stroke hydraulically operated pumping unit where the polished rod is confined to the extent that it is impossible to couple the dynamometer directly thereto.

The long stroke hydraulically operated pumping unit comprises a vertical hydraulic cylinder of approximately 24 feet in length. The polished rod is connected to a hydraulically operated piston which is confined within the vertical cylinder; thus, proper application of the hydraulic pressure at the bottom and top of the piston will cause the polished rod to reciprocate thereby providing pumping action for an oil well. In order to properly weigh the oil well, it has been the practice in the field to couple a dynamometer directly on the polished rod. As the pumping unit operates, the dynamometer measures the force required to operate the pump throughout its entire cycle. The dynamometer commonly used for this purpose, however, is coupled directly to the polished rod and reciprocates with the polished rod since the rod, for the usual beam type pump, has its upper portion completely exposed during the entire cycle. A dynamometer commonly used in the field for this purpose is manufactured by the Johnson-Fagg Engineering Company, Tulsa, Oklahoma, United States of America, and is clearly described in United States Patent No. 2,659,233 issued November 17, 1953.

Briefly, the dynamometer comprises a bifurcated proving ring as the force measuring medium. The proving ring is adapted to straddle the polished rod of the oil Well pump and is adapted to be placed in compression along the diameter parallel to the polished rod. Thus, as the pump reciprocates, the force required to operate the pump is transmitted through the bifurcated ring to the dynamometer. Means is also incorporated into the dynamometer to measure the total stroke so that a graph of stroke distance versus horse power is plotted on the dynamometer.

Unfortunately, the hydraulic pumping units as described have only a portion of the polished rod exposed; thus, it is impossible to connect the dynamometer to the polished rod in any feasible manner to attain a reliable graph of the force versus pumping stroke of the pumping unit.

Therefore, it is an object of this invention to provide adapting a standard dynamometer to a hydraulic pumping unit so that a proper measurement can be made of the pumping unit.

t is a further object of this invention to provide a simple adapter that can be utilized with any ring type dynamometer for the weighing of wells using hydraulic pumping units.

This invention features a C type clamp which has a vertical rod through one of the base members, and which has the approximate size of the polished rod. Above the vertical rod is a hydraulically operated piston. A hydraulic hose is connected between the pumping unit and the piston for the purpose of communicating variations in pressure from the hydraulic pumping unit to the adapter. The dynamometer bifurcated proving ring is inserted transversely through the C clamp about the vertical piston with the pressure transmitting piston pressed against the upper portion of the ring. The stroke transmission mechanism is removed and a friction wheel is substituted therefor. Thus, variations in pressure, indicative of the horse power required to operate the polished rod, are transmitted to the piston resulting in a corresponding variation in compression across the bifurcated ring. The friction wheel is pressed against the exposed portion of the polished rod and communicates the information concerning the length of the stroke to the dynamometer.

Other objects, features, and advantages of the invention will become apparent from the following description and claims when read in view of the accompanying drawings, in which:

FIG. 1 is a front view of a hydraulic pumping unit showing the front view of the dynamometer and adapted as applied to the pumping unit;

FIG. 2 illustrates a side view of FIG. 1;

FIG. 3 is a partial sectional view of the dynamometer proving ring clamp;

FIG. 4 is a three-dimensional view of the proving ring clamp; and

FIG. 5 is a three-dimensional view of the dynamometer clamp and friction engaging ring in actual use against a polished rod.

Referring to the figures in general and particularly to FIG. 1, a hydraulic pumping unit 10 is mounted by a tripod or other usual method (not shown) above the well to be pumped. A piston (not shown) within the hydraulic pumping unit is connected to a polished rod 11 which is in turn connected through the casing and packing 13 to a pumping unit lower in the well (not shown). Attached to the pumping unit for the purposes of weighing the well is a dynamometer, generally referred to as 12. The basic units of the dynamometer comprise the bifurcated proving ring 14, compression transmission arms 15, chart scribing box 16, and stroke coupling means 17. Surrounding the bifurcated ring is a. C type proving ring clamp 20. In place of the usual stroke transmission medium which usually comprises a string having a magnet attached to its end, is the friction engagement means 21.

The C type proving ring clamp, see FIGS. 3 and 4, comprises an upper portion 22, a lower portion 23, and a coupling member 24. A steel rod 25, which may, for example, be 1 /2 inches in diameter, is used to take the majority of the stress between the upper and lower portion of the proving ring clamp. A second rod 26 is mounted in the lower portion 23 of the proving ring clamp and is approximately the size of the polished rod, and may, for example, be approximately 1% inches in diameter. A piston 27 is mounted in the upper portion 22 of the proving ring clamp axially above rod 26. The piston is provided with a plurality of 0 rings 28 which are adapted to confine the hydraulic fluid within the cylinder 29. A valve 30 and inlet pipe 31 are connected to the upper portion of cylinder 29 and adapted to permit hydraulic fluid to communicate between cylinder 29 and pumping unit 10 through a means such as hose 33, see FIG. 2. Valve 34 may also be provided at the outlet of pumping unit 10 to provide an easy method for disconnecting hydraulic hose 33 when the dynamometer is to be removed. The length of rod 26 is best designed so that it will prevent piston 27 from falling out of cylinder 29 when the adapter is not in use. Rod 26 may be mounted in lower portion 23 by any suitable means such as threads 32. A handle 35 is also provided in the lower portion 23 to facilitate holding to dynamometer during the weighing of the well. Handle 35 likewise may be mounted into lower portion 23 by any suitable method such as threads 36. It is understood by those skilled in the art that many suitable methods are available for mounting rod 25, piston 27, and handle 35 and that these alternate methods are within the intended scope of this invention. It should be further understood that while the C type proving ring 20 is shown formed by a plurality of charts for ease in manufacturing, it would be Well within the ability of one skilled in the art to form the entire assembly by a single casing.

The dynamometer, when mounted within the adapter, may be either held against the polished rod, see FIG. 5, until a proper graph or chart is obtained or it may be readily mounted to the casing head or pump by using a means such as braces 40, see FIG. 2, or other suitable mounting location if a more permanent installation is desired.

Operation In operation, the dynamometer bifurcated proving ring 14 is inserted transversely into the proving ring clamp 20 about piston 27 such that about half of the ring is on either side of piston 27. A T type spring loaded clamp 37, see FIG. 5, may be inserted between the rod 26 and the forward edge of ring 14 in order to rigidly secure the ring to the clamp. Piston 27 should rest against the top of ring 14. The stroke coupling means, which is usually in the form of a wheel mounted to the chart control means 16 and has a length of string wrapped about its diameter, is removed and friction engagement ring 21 is substituted therefor. The friction engagement ring is much larger than the coupling ring usually used on such dynamometers and for most purposes may be approximately 19 /2 inches in diameter. The outer periphery of the ring should be made or covered with a material that will provide adequate frictional engagement when pressed against polished rod 11. Pressure variations within the piston are transmitted through hydraulic hose 33 from the bottom of valve outlet 34 in pumping unit 10 and connects to cylinder 29 through valve 30. If an outlet 34 is not provided at the outlet of pumping unit 10, a valve can be easily secured in the above described fashion. With the pressure communicating means to the hydraulic hose connected, the friction engagement means 21 is pressed against the polished rod 11 and held in this position during the entire cycle. Of course, if a more permanent position is desired, the dynamometer may be mounted by brackets 40. Thus, when the polished rod 11 moves in an upward direction, the increase in pressure is transmitted through hydraulic hose 33 to piston 27, which in turn transmits the increased pressure to proving ring 14. The increase in compression across ring 14 is transmitted through appropriate levers to the piston mechanism confined within housing 16. In order to apply the stroke to the chart mechanism, movement of the polished rod is communicated through the friction engagement means 17 to the chart mechanism confined within housing 16. Upon completion of the graph, the entire assembly is removed from engagement with the polished rod 11, valve 34 is shut off, and hydraulic hose 33 is disconnected.

The length of the stroke transmitted to chart mechanism within housing 16 can be easily varied by a change in the diameter of friction engagement means 21. This might be necessary if the length of the graph were to be increased for a shorter stroke mechanism. The compression sensitivity of the dynamometer can be readily increased by a variation in the diameter of the piston 27. Thus, for a smaller unit, the diameter of the piston can be increased, thereby giving a higher sensitivity to the chart recording mechanism 16. The device is simple to maintain, since the piston can be readily removed and the rings 28 replaced when necessary by removing the center rod 26, thereby permitting the piston to drop out of cylinder 29.

Throughout the application, the adapter has been described as having a C shaped frame. The open end facilitates ease in mounting the adapter to a standard dynamometer. If the open end were closed, it would interfere with the stroke coupling means 17. However, it should be obvious to those skilled in the art that if an extension were added to the shaft supporting stroke coupling means 17 that the open end of C shaped adapter 20 could easily be closed. Therefore, this invention is not specifically limited to a C shaped type adapter but rather to an adapter capable of supporting a dynamometer and having a hydraulically operated piston which is adapted to apply vertical pressure to the bifurcated ring.

Although this invention has been described with respect to particular embodiments thereof, it is not to be so limited, as changes and modifications may be made therein which are within the spirit and scope of the illvention as defined by the appended claims.

I claim:

1. An adapter for a mechanically operated dynamometer to permit said dynamometer to weigh a hydraulic pumping unit for a well, said adapter comprising a clamp having a bottom and top portion, means for rigidly supporting said bottom and top portions in parallelly spaced relationship, said bottom portion having a groove along its length to support a dynamometer ring transversely thereagainst, a post having a length less than the distance between the bottom and top portions and mounted perpendicularly into said groove along said bottom portion and parallel to said supporting means, a cylindrical piston chamber formed in said upper portion opposite said post and substantially axially with said post, a piston confined within said piston chamber and adapted to move towards or away from the end of said post, and a hydraulic input mounted on said upper portion and communicating with said piston cylinder, wherein a dynamometer bifurcated proving ring when transversely clamped between the groove and said bottom portion, and the piston in said top portion will have compressible force applied across its diameter in correspondence with a variation in the hydraulic pressure of said hydraulic pumping unit.

2. A dynamometer adapted for a hydraulic pumping unit, said dynamometer being of the type having a bifurcated proving ring, a dynamometer chart assembly operatively connected to said bifurcated proving ring and a polished rod displacement means operatively connected to said dynamometer chart assembly, said adapter comprising: a clamping means having first and second opposing faces adapted to clamp a bifurcated ring therebetween, a locating post mounted on one end and normal to said first opposing face, a cylindrical piston confining chamber formed in the second opposing face and axially aligned with said post, said chamber containing a piston therein which is adapted to move toward or away from the first opposing face, hydraulic fluid communicating means mounted on said clamping means and communicating with said piston confining chamber wherein the separated portions of said bifurcated ring are located on each side of said locating post and said ring centered diametrically between said first opposing face and said piston such that a variation of hydraulic fluid communicating to said chamber will cause a variation in the pressure exerted by said piston against said ring, the compressive variation of said ring being recorded on said recording chart along with information from said polished rod displacement means.

3. A dynamometer as defined in claim 2 wherein said polished rod displacement means comprises a circular disc having a frictionally engaging surface on its periphery, and characterized further to include means for pressing the friction engaging surface of said disc against the polished rod of the hydraulic pumping unit for operating the dynamometer chart assembly in accordance with the strokes of said polished rod.

4. A dynamometer adapter comprising a C shaped clamp having a base, side, and top, a locating post mounted perpendicularly into said base and extending toward the top of said clamp, a piston cylinder formed in the top of said adapter substantially opposite and axially oriented with said post, a slidable piston means confined within said cylinder, and a hydraulic input means mounted on said C shaped clamp and communicating with said cylinder such that a variation in hydraulic pressure in the input of said hydraulic input means will cause a corresponding displacement in said piston wherein the separated portions of a bifurcated 5 pressure responsive ring may be placed about said locating post and clamped diametrically between said base and said piston, such that a variation in pressure delivered by said piston will cause a corresponding variation in the compressive forces across the diameter 10 of said bifurcated pressure responsive ring.

References Cited in the file of this patent UNITED STATES PATENTS Howard et al. Dec. 17, Lake Dec. 17, Kemler Dec. 8, Bonney et al. Nov. 23, Matner et a1. Jan. 2, Fagg et al. Nov. 17, Swanson May 31, Dumas July 24, 

1. AN ADAPTER FOR A MECHANICALLY OPERATED DYNAMOMETER TO PERMIT SAID DYNAMOMETER TO WEIGH A HYDRAULIC PUMPING UNIT FOR A WELL, SAID ADAPTER COMPRISING A CLAMP HAVING A BOTTOM AND TOP PORTION, MEANS FOR RIGIDLY SUPPORTING SAID BOTTOM AND TOP PORTIONS IN PARALLELLY SPACED RELATIONSHIP, SAID BOTTOM PORTION HAVING A GROOVE ALONG ITS LENGTH TO SUPPORT A DYNAMOMETER RING TRANSVERSELY THEREAGAINST, A POST HAVING A LENGTH LESS THAN THE DISTANCE BETWEEN THE BOTTOM AND TOP PORTIONS AND MOUNTED PERPENDICULARLY INTO SAID GROOVE ALONG SAID BOTTOM PORTION AND PARALLEL TO SAID SUPPORTING MEANS, A CYLINDRICAL PISTON CHAMBER FORMED IN SAID UPPER PORTION OPPOSITE SAID POST AND SUBSTANTIALLY AXIALLY WITH SAID POST, 